1. Technical Field
The present invention relates to a projector.
2. Related Art
In the related art, a projector is provided with a circulation-type liquid-cooling device to circulate cooling liquid along a flow path such that a cooling target such as a liquid crystal panel is effectively cooled down by the circulated cooling liquid.
In such a liquid-cooling device, cooling liquid may evaporate as the cooling liquid has been used over the years. In this case, bubbles may occur in the flow path. Furthermore, when the amount of bubbles increases, it makes it difficult for the cooling liquid to circulate along the flow path. As a result, the cooling efficiency for the cooling target may decrease.
Therefore, in the related art, a technique in which a reserve tank (liquid storage unit) captures bubbles so as to remove bubbles in the flow path has been adopted (refer to JP-A-2005-331928).
Specifically, the liquid storage unit disclosed in JP-A-2005-331928 includes a tank which temporarily stores cooling liquid therein and inflow and outflow nozzles through which cooling liquid flows into and out of the tank.
When cooling liquid containing bubbles flows into the tank, the bubbles move to the upper space inside the tank due to their buoyancy. At this time, the bubbles are captured in the space, and only the cooling liquid flows to the outside through the outflow nozzle.
The liquid storage unit disclosed in JP-A-2005-331928 has been designed on the assumption that a projector projects an image at a normal posture such that the image is projected in a substantially horizontal direction. At the normal posture, the projector is loaded on an installation surface of a desk or the like. In other words, the liquid storage unit is designed in such a manner that when the projector is installed at the normal posture, bubbles are captured in the tank and only the cooling liquid flows out of the tank.
Therefore, when the projector is installed at an upward projection posture where the projector projects an image upward or a downward projection posture where the projector projects an image downward, bubbles may flow out of the tank. At the upward projection posture, a projection lens is positioned upward. At the downward projection posture, the projection lens is positioned downward.
Specifically, the liquid storage unit disclosed in JP-A-2005-331928 is constructed in such a manner that the outflow nozzle is provided in a direction along the projection direction with respect to the tank, and the cooling liquid flows out to the opposite side of the projection direction. Therefore, when the projector is installed at the downward projection posture, the liquid storage unit is postured in such a manner that the outflow nozzle is positioned on the upper side wall in the tank, and the cooling liquid flows out from the upper side through the outflow nozzle. That is, bubbles flowing with the cooling liquid into the tank move to the internal space of the tank at the upper side (where the outflow nozzle is positioned) due to their buoyancy, and then flows to the outside through the outflow nozzle.
Therefore, a technique is being demanded, which prevents bubbles captured by the liquid storage unit from flowing out of the liquid storage unit, and effectively cools down a cooling target using cooling liquid, even when the projector is installed at various postures.